Error in fitting submodels

hi hermine,
I think the problem is passing in the name of the model you want to use as a basis for the new model as a string: It is then treated as the name of a new model.

so
mxModel(oldMod, changes...)
not
mxModel("oldMod", changes...)

Using a monolithic supermodel (i.e., building the submodels inside the supermodel, instead of building them outside and then importing them into slots in a new supermodel makes updating harder.

Have a look at the current state of the trunk/demo/ twin examples now: They are restructured to decompose the shared and group-specific elements into seperate models, and then to update and combine these as needed in supermodels.

I attach a hack on the script you attached above as an example of this type of restructuring.

nb (from ?mxModel)

model This argument is either an MxModel object OR a string. If 'model' is an MxModel object, then all elements of that model are placed in the resulting MxModel object. If 'model' is a string, then a new model is created with the string as its name. If 'model' is either unspecified or 'model' is a named entity, data source, or MxPath object, then a new model is created.